Front end loaders



Feb. 19, 1963 G. R. DEMPSTER ETAL 3,0 0

FRONT END LOADERS Filed July 14. 1959 2 Sheets-Sheet 1 ATTORNEYS FRONT END LOADERS Filed July 14, 1959 2 Sheets-Sheet 2 ATTORNEYS United States Patent 3,078,009 FRGNT END LOADERS George Dempster, William A. Herpieh, and Neil F. Wonder, Knoxviiie, Tenn; said Wonder and said Eerpieh assignors to Dempster Brothers, lno, Knoxville, Tenn, a corporation of Tennessee Filed July 14, 1959, Ser. No. 827,0tt7 3 Claims. (til. 214-602) This application is a continuation-in-part of our former application, Serial No. 662,252, filed May 28, 1957, now Patent No. 2,900,096.

This invention relates to improvements in front end loaders of the character used for picking up containers at the front end of a motor vehicle and dumping the contents therefrom into the body of the vehicle.

In former devices as manufactured heretofore, lifting arms have been provided on a motor vehicle, pivotally mounted on the chassis of the vehicle for rotary movement about an axis located behind the cab and adjacent the chassis frame. At the opposite ends of the lifting arms, fork arms are mounted on a torque tube journaled in the front end portions of the lifting arms and operated to provide for swinging movements with respect to the lifting arms. These fork arms engage a container and lift the container during the dumping cycle of movement.

The lifting arms provided heretofore usually have been operated by a cylinder or cylinders mounted on the chassis frame, acting through lever members which project below the axis of rotation of the lifting arms and connected with the latter through a torque tube or directly. In such case, the cylinders are operated on a pushing motion imparted to the lever arms for raising the lifting arms.

One object of this invention is to reduce the amount of force required to lift the arms with their maximum load and to provide a front end loader structure lighter in weight and at less cost.

This object may be accomplished by mounting the power cylinders directly in line with the lifting arms and connecting the cylinders directly with the lifting arms through the plates mounted thereon.

In such front end loader mechanism, it has been customary practice to dump the contents of the container directly into the body through an opening or hopper provided thereon. Frequently, due to variations in the relative size of the container and the hopper opening, it is difiicult to direct the container far enough into the hopper opening to prevent blowing of the material out of the compaction body as it is being discharged from the container.

Another object of the invention is to provide shielding means in such position during dumping of the container as to prevent the blowing of the material out of the compaction body and yet will not cause extra height on the compaction body itself during operation of the equipment in traveling position.

This object may be accomplished by providing a pair of shields fastened to the lifting arms and carried by the latter, so that normally these shields are below the top of the body during movement of the vehicle in traveling position, but are so disposed as to cause a directing of the refuse in the body when the container is moved to its discharge position.

3,078,000 Patented Feb. 19, 1963 One embodiment of this invention is illustrated in the accompanying drawings, in which:

FIG. 1 is a side elevation of a vehicle to which the invention is applied;

FIG. 2 is a partial top plan view thereof, showing a portion of one of the lifting arms and its operating cylinder, and taken substantially on the line 2--2 in FIG. 1;

FIG. 3 is a detail side elevation showing the lifting arms in dumping position;

FIG. 4 is a cross section thcrethrough on the line 4--4 in FIG. 3; and

FIG. 5 is a cross section on the line 55 in FIG. 3.

The invention is shown as applied to a motor vehicle of conventional form, merely as an example of the type of vehicle on which this loading device may be used. It has been customary heretofore to utilize a vehicle chassis of the character generally indicated by the numeral 1, and it has a chassis frame supported by road wheels 2 and which is self-propelled. The vehicle has the usual cab 3 for accommodation of the operator.

A refuse body is shown at 4 mounted on the chassis 1. This may be any suitable or desired type of body adapted to receive refuse therein, such as garbage, trash, and the like, and may be of the character that is provided with power means to compress the refuse as it is deposited in the body. It is preferred that the body 4 be of the type which has a filling opening or hopper, generally indicated at 5, in the top thereof near the front through which the refuse can be directed into the body.

The loader structure comprises a pair of lifting arms 6 spaced apart a distance substantially of the width of the cab 3. These arms 6 preferably are of gooseneck shape or of inverted U-shape, so as to extend upwardly and downwardly in back of the cab 3, substantially as illustrated in FIG. 1. The arms 6 preferably should clear the cab fully and should be located within the lateral confines of the body.

At their back ends, the arms 6 extend downwardly to a transverse torque tube or pivot, generally indicated at 7, journaled in suitable bearings on the chassis frame 1 or in the base frame of the body 4. This torque tube 7 preferably extends transvsersely of the vehicle throughout the width thereof and has the lower ends of both opposite lifting arms 6 mounted or journaled thereon for independent or joint operation, as desired. -It is preferred that these be fixed to the torque tube for unitary operation, although they may function independently, if preferred.

The lifting arms 6 are adapted for operation by hydraulic cylinders 8, one for each lifting arm. Each of the cylinders 8 has its closed end anchored at 9 on a pivot secured to the base frame of the body 4, as illustrated in FIGS. 1 and 2 of the drawings. Each cylinder 8 extends forwardly from the pivot 9 and has its piston rod 10 extending in direct longitudinal alignment with the adjacent lifting arm 6, as will be apparent from FIG. 2.

The front end of the piston rod 10 is connected with a pivot pin 11 that extends between tie plates 12 secured by welding or otherwise in embracing relation with opposite sides of the adjacent lifting arm 6, substantially as illustrated in FIG. 1. The pivot axis 11 is on the opposite side of an upright transverse plane through the axis of the torque tube 7 from the cylinder 8, when the lifting arms 6 are in their lowered positions for picking advance 3 up a container. The location of the tie plates 12, somewhat above the torque tube 7, disposes the line of the cylinder 8 and piston rod 10 at a sufiicient angle to impart the required pulling and pushing motions to effect movement of the lifting arms even under the weight normally encountered.

This connects the main lifting arm cylinder 8 directly with each of the lifting arms and provides an effective connection which reduces the amount of force required to lift the arm with its maximum load. This results in a loader structure which is lighter in weight and one that may be built at less costthan the construction provided heretofore.

At the front end portions of the lifting arms 6, these lifting arms are connected together by a torque tube 13 adapted to be operated by power cylinders 14. Mounted on the torque tube 13 are fork arms 15 adapted for detachable engagement with a container sitting on the ground for picking up and dumping the container into the hopper or opening 5. The fork arms 15 are in an intermediate position in FIG. 1. During normal picking up of the container, these fork arms would be moving substantially to horizontal position by the cylinders 14.

In dumping the container, the lifting arms 6 are elevated from the full line positions shown in FIG. 1, substantially to the dotted line positions therein, and appropriate movement of the fork arms 15 would also be effected relative to the lifting arms 6 for accomplishing this dumping action.

With some types of containers and. due to the dumping action involved by the operator, some of the refuse may be blown out of the hopper opening of the body with the loader structure provided heretofore. Extensions on the top of the hopper would be objectionable in many instances, due to the added height that would be required for the body, especially in traveling position.

This diificulty has been solved, according to this invention, by providing elongated plate-like hopper extensions, generally indicated at 16, on the respective lifting arms 6 and secured thereto, so as to be carried by these lifting arms. Each hopper extension 16 extends at an acute angle to the length of the downturned front end portion of each lifting arm 6 and is so mounted with respect thereto as to be disposed substantially horizontal over the adjacent edge of the hopper when the lifting arm is in its dumping position, as shown in dotted lines in FIG. 1 and in full lines in FIG. 3.

Each hopper extension 16 may be in the form of an elongated plate, solid, perforated, reticulated, expanded metal, etc. In the form shown as an example, it is suitably braced by outturned flanges 17 on the periphery thereof and with intermediate bracing at 18. The lower edge of the hopper extension 16 may be provided with a flexible sealing strip, of rubber or other suitable material, indicated generally at 19, secured to the lower edge of the hopper extension 16 and extending downwardly therefrom in position to be directed into the hopper 5.

The rear portion of each hopper extension 16 is mounted on a spacer bracket 20 which extends laterally therefrom and has a connection with the hopper extension substantially throughout the height thereof, as will be apparent from FIG. 4. The spacer bracket 20 extends laterally from the hopper extension 16 and is welded or otherwise secured to the adjacent anchor plate 21 which secures the adjacent cylinder 14 to the lifting arm 6. The front end portion of the hopper extension 16 is also anchored to the lifting arm 6 by a spacer block, indicated at 22 in FIG. 5, which may be welded to the lifting arm 6.

The lifting arms 6 are shown as provided with stop members, indicated at 23, on the inner faces thereof beside the hopper extensions 16 in positions to strike the top of the hopper and limit the movement in one 4 direction, with the lifting arms in proper dumping positions.

When the lifting arms 6 are in their dumping positions, these hopper extensions 16 will prevent the flowing of material out of the hopper and assure that the contents will be dumped effectively from the container into the body of the vehicle. They may extend upward sufficiently high so as to receive the container therebetween and afford the required extension on the hopper for the elfective discharge of the contents. At the same time, these extensions, being carried on the front end portions of the lifting arms, Will be lowered with the lifting arms, so as to have a standard low-sided hopper when the arms are down in traveling positions. The extensions will not add appreciably to the Weight of the arms, being formed of light-weight sheet metal, screen, or expanded metal, etc., and, therefore, may be raised and lowered with substantially no increase in force required and are effective for the purpose described.

While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein, without departing from the invention as set forth in the claims.

We claim:

1. In a front end loader of the character described, the combination with a motor vehicle of the type having a chassis frame, a body on the frame having an opening therein adapted to receive material, of a load ing mechanism comprising lifting arms pivotally mounted on the vehicle, fork arms pivotally mounted on the outer ends of the lifting arms, said lifting arms and fork arms being swingable between a lowered position in which the fork arms are in position to engage and pick up a separate container and a raised position to dispose the container in a dumping position, and means carried by the lifting arms during said raising movements to be disposed horizontally over and forming spaced extensions on the lateral sides of said opening, and means to swing said fork arms as the lifting arms approach their raised position to dispose said container in an inverted position relative to said horizontally disposed extension means.

2. In a front end loader of the character described, the combination with a motor vehicle of the type having a chassis frame, a body on the frame having an opening therein adapted to receive material, of loading mechanism comprising lifting arms pivotaliy mounted on the vehicle, fork arms pivotally mounted on the outer ends of the lifting arms, said lifting arms and fork arrns being swingable between a lowered position in which the fork arms are in position to engage and pick up a separate container and a raised position to dispose the container in a dumping position, upright spaced extension members extending transversely of the lifting arms and in position to lie horizontally over and in vertical alignment with lateral opposite sides of the opening, bracket means mounting the extension members on the arms for raising and lowering movements therewith, and means to swing said fork arms relative to the lifting arms as the lifting arms a proach their raised position to dispose said container in an inverted position with said horizontally disposed extension members resting on the body.

3. In a front end loader of the character described, the combination with a motor vehicle of the type having a chassis frame, a body on the frame having an opening therein adapted to receive material, of a loading mechanism comprising lifting arms pivotally mounted on the vehicle for swinging movement between a lowered position in which the lifting arms are in position to engage and pick up a separate container and a raised position in which the lifting arms are in position to dump said container through the opening into the body, upright hopper extension members extending transversely of the lifting arms and disposed between the arms substantially in vertical alignment with opposite sides of the opening,

bracket means mounting the extension members on the arms for raising and lowering movement therewith, said arms moving the extension members substantially into engagement with the opening when the arms are in container dumping positions, and flaps carried by the extension members in positions to extend into the opening and form continuations thereon to direct the material into the opening.

References Cited in the file of this patent UNITED STATES PATENTS Healy Feb. 9, 1897 Owen May 18, 1948 Crosby Oct. 16, 1951 Beasley Feb. 25, 1958 Aldredge et al May 5, 1959 Dempster et a1 Aug. 18, 1959 

1. IN A FRONT END LOADER OF THE CHARACTER DESCRIBED, THE COMBINATION WITH A MOTOR VEHICLE OF THE TYPE HAVING A CHASSIS FRAME, A BODY ON THE FRAME HAVING AN OPENING THEREIN ADAPTED TO RECEIVE MATERIAL, OF A LOADING MECHANISM COMPRISING LIFTING ARMS PIVOTALLY MOUNTED ON THE VEHICLE, FORK ARMS PIVOTALLY MOUNTED ON THE OUTER ENDS OF THE LIFTING ARMS, SAID LIFTING ARMS AND FORK ARMS BEING SWINGABLE BETWEEN A LOWERED POSITION IN WHICH THE FORK ARMS ARE IN POSITION TO ENGAGE AND PICK UP A SEPARATE CONTAINER AND A RAISED POSITION TO DISPOSE THE CONTAINER IN A DUMPING POSITION, AND MEANS CARRIED BY THE LIFTING ARMS DURING SAID RAISING MOVEMENTS TO BE DISPOSED HORIZONTALLY OVER AND FORMING SPACED EXTENSIONS ON THE LATERAL SIDES OF SAID OPENING, AND MEANS TO SWING SAID FORK ARMS AS THE LIFTING ARMS APPROACH THEIR RAISED POSITION TO DISPOSE SAID CONTAINER IN AN INVERTED POSITION RELATIVE TO SAID HORIZONTALLY DISPOSED EXTENSION MEANS. 